1. Field of the Invention
The present invention relates to a stage apparatus, a lithography apparatus, and a method of manufacturing an article.
2. Description of the Related Art
A lithography apparatus used to manufacture a semiconductor device or liquid crystal device positions a substrate held by a substrate stage, and performs a process (for example, exposure) of transferring a pattern on the substrate. The substrate stage generally includes a coarse moving stage which performs large-stroke movement, and a fine moving stage which performs high-precision positioning on the coarse moving stage. Movement by the fine moving stage is performed by driving a linear motor. In terms of vibration transmission, a linear motor magnet is arranged on the fine moving stage side, and a linear motor coil is arranged on the coarse moving stage side.
Such a substrate stage has the problem of heat generation of the linear motor (that is, linear motor coil). To solve this, Japanese Patent No. 3278380 proposes a cooling mechanism which recovers heat from a linear motor coil. The cooling mechanism disclosed in Japanese Patent No. 3278380 covers the space around the linear motor coil with a jacket, and the space is filled with a fluid refrigerant to recover heat from the linear motor coil.
When the space around the linear motor coil is filled with a fluid refrigerant, a coating process is required to form a coating on the lead wire of the coil so the lead wire of the coil and the refrigerant do not directly contact each other. However, if the coating formed by the coating process is damaged in the assembly of a substrate stage, the lead wire of the coil and the refrigerant contact each other, and the lead wire of the coil sometimes corrodes and is disconnected. The coating itself is highly likely to corrode upon exposure to the refrigerant for a long period. If the coating corrodes, the coil may short-circuit. It is therefore difficult to maintain the reliability of the substrate stage in the cooling mechanism requiring a coating process on the lead wire of a coil.